1. Field of the Invention
This invention relates to a single-piece-transfer type carrier for transferring plate-like objects such as semiconductor wafers or liquid crystal display elements, one by one from one place to another. It also relates to a handling apparatus of a carrier for transferring plate-like objects such as semiconductor wafers, one by one, to and from an apparatus for inspection, processing or the like. Further, this invention relates to a probing apparatus, equipped with a carrier handling apparatus capable of sampling plate-like objects such as semiconductor wafers, one by one, as necessity requires.
2. DESCRIPTION OF THE RELATED ART
Generally, in the manufacturing process of semiconductor devices such as ICs and LSIs, a number of semiconductor wafers are accommodated in a wafer cassette and are transferred contained in the cassette from apparatus to apparatus, and from one process to another.
In a full-automatic probing machine for testing wafers, for example, a special-purpose handling apparatus takes wafers out, one by one, from a wafer cassette set in the loading/unloading section. Then, the wafer is subjected to pre-alignment, placed on the main chuck of the testing section and receives a probing test. After the test is finished, the wafer is taken back by the full-automatic transferring apparatus and returned to a wafer cassette.
In other words, in the full-automatic wafer probing machine, semiconductor wafers are taken out one after another from wafer cassettes and put back into the cassettes without the operator directly touching the wafers by hand.
With conventional full-automatic wafer probing machines, wafers cannot be taken out without opening the machine. These conventional wafer probing machines are suitable for mechanically processing a large quantity of semiconductor wafers, but they have difficulty in handling individual wafers. When taking out individual wafers for manual measurement or picking out a single sample from among many wafers using a conventional wafer probing machine, the operator has to take a wafer out with forceps (tweezers).
In the manual transfer of wafers to a subsequent process, the operator needs to exert his power of concentration and must be skilled in the work. Even though he exercises due care in manual transfer, it sometimes occurs that a wafer is damaged when it slips off forceps or collides with something else.